Under the Affordable Care Act (ACA), Medicaid plays a key role in efforts to reduce the number of uninsured by expanding eligibility to nearly all low income adults with incomes at or below 138 percent of the federal poverty level ($16,242 per year for an individual in 2015) with 100 percent federal financing for the first three years, gradually decreasing to 90 percent. However, the 2012 Supreme Court ruling on the ACA’s constitutionality effectively made the expansion a state option. As of December 2015, 31 states including DC have adopted the expansion, and nearly all are implementing it as set forth by the law. A limited number of states have obtained or are seeking approval through Section 1115 waivers to implement the expansion in ways that extend beyond the flexibility provided by the law. In some cases, these alternative models to implement the expansion are seen as a politically viable way to extend coverage and capture enhanced federal matching funds for newly eligible adults. This page highlights some key resources examining ACA Medicaid expansion waivers and, farther down, also provides the standard search result page for a site-wide search on the “waivers” tag.